Welcome to CQRS Site. This is a community-driven effort to document patterns and practices around Command-Query Responsibility Principle. [Learn more].

The site consists from CQRS Story (continuous stream of updates and practical tips shared by Lokad) and community-driven CQRS Pocket Book (being owned, updated and maintained by the community). Views on this web site might be different from views outlined in Microsoft CQRS P&P guidance or some other enterprise-level resources on CQRS. This story focuses on simple and practical things that help a tiny company to build amazing things, while staying lean, hungry and surviving everyday battle with much larger competition.

This reference is based on concepts that have been around software industry for decades and were pushed further by amazing people like Greg Young, Eric Evans and a lot of other friends and practitioners from around the world. Kudos and thanks go to them for sharing their knowledge, experience and helping to push the state of the art.


Once upon a time, there was an open source project called [Lokad.CQRS Sample Project]. It was maintained by a small start-up company that learned a lot from the community and wanted to give something back.

The project was reasonably good, since it was an extract from production code, that could run in multiple clouds, survive various crashes and still be maintained by less than one developer. It was consistently updated with various practical tweaks and hacks that proved to be useful in real life. Other skilled teams around the world were even daring to apply the project as a guidance and jump-start template to in their own endeavors.

Still, there was a huge flaw in Lokad.CQRS - it was too complicated for those new to the art. And it lacked almost any theory or detailed explanations. These were sad days for the community, since other sources of information were either [being delayed] or just getting started.

Then community suggested to gather up and finally start pushing forward a community-driven resource that could help to properly document [CQRS Firehose], while providing better coverage of the basics and patterns, sharing insights provide detailed help for those who are interested to learn and may be even [give back].

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License